The Role of Occult Cardiac Amyloid in the Elderly With Aortic Stenosis.

Aortic Stenosis Clinical Trial

— ATTRact-AS  

Official title:

A sTudy invesTigating the Role of Occult cArdiaC Amyloid in The Elderly With Aortic Stenosis

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03029026
• Other study ID #: 006974
• Status: Recruiting
• First received: January 9, 2017
• Last updated: April 17, 2018
• Start date: September 2016
• Est. completion date: April 2019

Study information

• Verified date: November 2016
• Source: Queen Mary University of London
• Contact: Paul R Scully, MBBS MRes
• Phone: 020 3465 6115
• Email: paul.scully[@]bartshealth.nhs.uk
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Aortic stenosis (AS) is the most common valvular heart disease. Once symptomatic with severe AS, outcome is poor unless the valve is replaced surgically or via transcatheter aortic valve replacement (TAVR). Transthyretin amyloid (ATTR) deposits are common in the heart muscle in up to 25% of octogenarians, and after an asymptomatic period of unknown duration, cause overt heart failure and arrhythmias in a proportion of cases. The prevalence and impact of covert ATTR amyloidosis in elderly individuals with AS are unknown. Detection would avoid misdiagnosis, guide treatment and, potentially, improve outcomes. Recent data have shown that echocardiography, cardiovascular magnetic resonance (CMR), computed tomography (CT), and DPD scintigraphy, can identify ATTR amyloid deposits, but the clinical performance of these various tests is unknown.

This study will investigate elderly patients with symptomatic severe AS using imaging to explore ATTR amyloid in AS and determine its prevalence and impact on outcome.

The investigators aim to recruit a total of 250 patients aged 75 or older being considered for intervention for severe AS. The prevalence of cardiac amyloid will be assessed in three arms (sAVR, TAVI and medical therapy, with a likely patient ratio of 50:150:50), using five investigation modalities - all cohorts (echocardiography and DPD scintigraphy); sAVR cohort (biopsy and CMR); TAVI cohort (EqCT); medical therapy only cohort (as per work-up/trial prior to no intervention decision).

The primary outcome measure is patient mortality. Secondary outcomes measures are major adverse cardiovascular events, length of stay, pacemaker implantation, ECV measured by EqCT and CMR.

Follow up will be at 1-year with clinical echocardiogram (for sAVR and TAVI patients) and/or telephone interview for all patients (if not carried out in person at the time of the echocardiogram).

Description:

INTRODUCTION

Calcific aortic stenosis (AS) is the most common valve disease in the West with a prevalence of 2.8% in patients over 75 years. Once symptomatic with severe AS, outcome is poor, unless the valve is replaced surgically (sAVR) or via transcatheter aortic valve replacement (TAVR), which is predominantly used in elderly patients for whom surgery is deemed too high risk.

Systemic amyloidosis is a multisystem disease characterised by extracellular deposition of abnormally folded protein, which over time results in progressive organ dysfunction. These protein deposits bind Congo red stain, producing the pathognomonic apple-green birefringence under polarised light. Cardiac involvement is the leading cause of morbidity and mortality in these patients. Amyloidosis due to transthyretin deposition (ATTR) can be due to wild-type transthyretin amyloid deposits, also known as senile systemic amyloidosis, which predominantly accumulates in the heart. Primary light chain (AL) amyloidosis and hereditary transthyretin amyloidosis can also affect the heart.

Wild-type ATTR (wtATTR) amyloid deposition is present in up to a 25% of individuals aged over 85 at autopsy. To date, this has been no more than an academic observation, but technology is changing this: cardiac imaging, particularly cardiovascular magnetic resonance (CMR) and 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scintigraphy, can now detect the disease antemortem, which is generating a major increase in national awareness. There are also significant advances being made in the treatment of amyloidosis. There are several drugs in clinical trial including novel antisense and interfering RNA therapeutics that can reduce production of TTR by up to 80-90%. Also on the horizon are treatments to promote clearance of established amyloid, notably including monoclonal anti-SAP (serum amyloid P component) antibodies. Despite the prevalence of wtATTR amyloid deposits at autopsy, their clinical significance and prognostic impact of in severe AS has not been explored.

Co-existent cardiac amyloid and AS. Given the prevalence of wtATTR in octogenarians at autopsy, AS and wtATTR are likely to co-exist - the literature has early evidence for this. In a cohort of 20 patients with AS, who had undergone TAVI and subsequently valve explantation at autopsy (n=17) or surgery (n=3), cardiac amyloid was found in a third of these patients and was thought to contribute to death in the majority. Our research also supports this - the "RELIEF-AS" study. In 146 patients with severe AS undergoing sAVR, we found cardiac amyloid deposits in 6 patients. All were wtATTR, all calcific AS, with the youngest patient being aged 69. Comprehensive imaging was performed, which showed a diagnostic imaging hierarchy: echocardiography was non-contributory, CMR detected a third of cases, whereas DPD scintigraphy was positive in all four patients scanned (2 died before the test). Biopsy ATTR deposits were prognostic and the strongest predictor of adverse outcome - regardless of infiltration degree or its imaging detection: post sAVR 50% with wtATTR died by 1 year vs 9% without (p<0.001). Occult amyloid has also been implicated in the need for pacemakers in TAVR patients.

The availability of TAVI has extended the range of individuals that can benefit from intervention for AS, prolonging life. TAVR patients are generally older so more likely to have wtATTR. One recent abstract found a 16% (23% in men) prevalence of cardiac amyloid in in patients undergoing TAVR (n=75) using 99mTc-pyrophosphate scintigraphy (PYP, a bone tracer available in the USA, which is possibly inferior to DPD). WtATTR is also an increasingly recognized cause of heart failure with preserved ejection fraction (HFpEF). DPD scintigraphy in 120 hospitalized patients who also had LV wall thickness ≥12 mm and an EF ≥50%, showed that 16 patients (13.3%) showed moderate to severe myocardial uptake.

Why detect wtTTR amyloid in severe AS? There are two separate aspects of wtATTR in AS. First, wtATTR in patients with moderate AS may mimic severe AS, (particularly low-flow, low-gradient) causing misdiagnosis. Second, wtATTR may itself be a disease modifier, leading to a more severe phenotype with more heart failure, arrhythmia, and higher mortality. We think there is a large, now detectable, UK population of elderly patients undergoing sAVR or TAVR with a significant occult amyloid. This could influence therapeutic options (TAVR vs sAVR vs medical therapy), intervention timing and medications - specific amyloid therapies, drugs to avoid (e.g. digoxin and diltiazem).

How to detect wtATTR? There are multiple techniques that could detect cardiac wtATTR. Each has their pros and cons with different evidence bases. Our initial study used three imaging modalities and biopsy to detect the presence of cardiac amyloid in sAVR. DPD scintigraphy was the superior imaging modality, with the highest diagnostic sensitivity. There is now a rapidly growing body of evidence supporting DPD scintigraphy as the non-invasive investigation of choice for diagnosing cardiac ATTR. A recent multi-centre study of over 1,000 patients showed that bone scintigraphy had a >99% sensitivity for cardiac ATTR deposits and they proposed it should have a role in diagnosing the condition without the need for invasive cardiac biopsy, which has previously been considered the gold standard.

The investigators have recently created a new modality: equilibrium contrast computed tomography (EqCT), which requires a single extra image dataset of the heart to be taken 5 minutes after the routine TAVR work-up CT images are taken. Extracellular volume fraction (ECV) calculated by EqCT discriminated 100% between cardiac amyloid involvement and patients with AS in 53 patients.

TRIAL OBJECTIVES

Hypothesis:

In the elderly with severe AS being considered for intervention (TAVR, sAVR), wtATTR is:

• Common.

• Conveys a worse prognosis.

• Can be reliably detected non-invasively.

Aim:

To confirm the prevalence, clinical impact (procedural complications, symptom response to aortic valve replacement, 1-year mortality) and potential place of imaging (DPD scintigraphy, ECV by CT, CMR and echocardiography) in occult amyloid in severe AS.

STUDY PLAN

Design: prospective observational cohort with 1 year follow-up.

Population: patients aged 75 or older with severe AS referred to the Barts Heart Centre for consideration for intervention (sAVR or TAVR) or referred to the John Radcliffe Hospital in Oxford for consideration for TAVR.

Proposed sample size: two centre study (Barts Heart Centre and the John Radcliffe Hospital), 250 patients.

Recruitment: patients will be recruited from General Cardiology, TAVR and Cardiothoracic Surgery Outpatient Clinics. A large proportion of these patients are discussed in the Valve Multidisciplinary Team Meeting, which will provide another source of recruitment. This will take place over an 18-month period from August 2016 to February 2018.

Baseline assessment: will include clinical history, Quality of Life Questionnaire (EQ-5D/SF-12), a 6-minute-walk test, blood sampling for haematocrit, renal function, biomarkers (NT-pro-BNP and troponin), and biobanking (also for AL exclusions if scanning positive), a urine sample for biobanking (also for AL exclusion if scanning positive), as well as tests performed as the routine pre-operative work-up (clinical electrocardiogram, blood pressure to estimate global LV afterload, valvulo-arterial impedance).

Measures of exposure: the prevalence of cardiac amyloid assessed in three arms (sAVR, TAVI and medical therapy, with a likely patient ratio of 50:150:50), using five investigation modalities - all cohorts (echocardiography and DPD scintigraphy); sAVR cohort (biopsy and CMR); TAVR cohort (EqCT); medical therapy only cohort (as per work-up/trial prior to no intervention decision).

Follow-up: 1-year follow-up with clinical echocardiogram (for sAVR and TAVR patients) and/or telephone interview for all patients (if not carried out in person at the time of the echocardiogram). This will include a follow up Quality of Life Questionnaire as per baseline. If attending clinic or echocardiogram a 6-minute-walk test will also be performed. MACE and mortality endpoints will also be identified.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 250
• Est. completion date: April 2019
• Est. primary completion date: April 2019
• Accepts healthy volunteers: No
• Gender: All
• Age group: 75 Years and older

Eligibility

Inclusion Criteria:

• Aged 75 or above

• Severe aortic stenosis being considered for intervention

• Patient informed consent

Exclusion Criteria:

• Unable to provide informed consent

• Patient declined or withdrew consent (at any stage)

• Imaging modality specific contraindications:

1. Being considered for sAVR, however unsuitable for study CMR due to contraindications such as a device in situ, severe claustrophobia, renal impairment (eGFR <30) or previous severe gadolinium contrast allergy.

2. Being considered for TAVR work-up CT, however unsuitable for contrast due to previous severe iodinated contrast allergy. NB patients with significant renal impairment are given pre-hydration routinely by the managing clinicians.

Related Conditions & MeSH terms

• Amyloidosis
• Aortic Stenosis
• Aortic Valve Stenosis
• Cardiac Amyloidosis
• Constriction, Pathologic

Intervention

Other:
• Baseline assessment
Baseline assessment will include clinical history, Quality of Life Questionnaire (EQ-5D/SF-12), a 6-minute-walk test, blood sampling for haematocrit, renal function, biomarkers (NT-pro-BNP and troponin), and biobanking (also for AL exclusions if scanning positive), a urine sample for biobanking (also for AL exclusions if scanning positive), as well as tests performed as the routine pre-operative work-up (clinical electrocardiogram, blood pressure to estimate global LV afterload, valvulo-arterial impedance).

Procedure:
• Transthoracic echocardiography
Patients will undergo a clinical transthoracic echocardiogram for the assessment of AS severity and diastolic function in line with the British Society of Echocardiography guidance. Simultaneous, optimised 2-chamber, 3-chamber and 4-chamber views will need to be recorded (over 3 cycles) for strain analysis. Severe AS will be defined using standard echocardiography guidelines in conjunction with MDT consensus.
• 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid scintigraphy
Scanning will use a hybrid SPECT-CT gamma camera after intravenous injection of 700 MBq of DPD (effective dose 4mSv). Acquisition technique: 5-minute (early) and then 3-hour (late) whole body planar scans, followed by SPECT-CT of the heart. Qualitative visual (Perugini) scoring of the cardiac uptake is performed from the 3-hour whole body planar images and the SPECT-CT images.

Radiation:
• CT 3-5-minute post-contrast research sequences
Cardiac CT for ECV will use the dedicated cardiac CT scanner (Somatom FORCE; Siemens Medical Solutions, Germany). 3-5-minute post contrast research images will be taken at the end of the clinically indicated TAVR work-up CT.

Procedure:
• Cardiac Magnetic Resonance
CMR will be performed using a 1.5-T Aera for standard late gadolinium enhancement, as well as T1 mapping and ECV.
• Endomyocardial biopsy
Septal tissue specimens will be taken under direct vision by the surgical team using a 14-gauge coaxial needle system. Biopsies will be screened for amyloid by Congo red staining; if positive, tissue will be fully sub-typed (immunohistochemistry, mass spectrometry).

Other:
• Follow-up assessment
1-year follow-up with clinical echocardiogram (for sAVR and TAVI patients) and/or telephone interview for all patients (if not carried out in person at the time of the echocardiogram). This will include a follow up Quality of Life Questionnaire as per baseline. If attending clinic or echocardiogram a 6-minute-walk test will also be performed.

Locations

Country	Name	City	State
United Kingdom	Barts Heart Centre	London
United Kingdom	The John Radcliffe Hospital	Oxford

Sponsors (1)

Lead Sponsor	Collaborator
Queen Mary University of London

Country where clinical trial is conducted

United Kingdom, 

References & Publications (15)

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Banypersad SM, Moon JC, Whelan C, Hawkins PN, Wechalekar AD. Updates in cardiac amyloidosis: a review. J Am Heart Assoc. 2012 Apr;1(2):e000364. doi: 10.1161/JAHA.111.000364. Epub 2012 Apr 24. — View Citation

Castaño A, Bokhari S, Maurer MS. Could late enhancement and need for permanent pacemaker implantation in patients undergoing TAVR be explained by undiagnosed transthyretin cardiac amyloidosis? J Am Coll Cardiol. 2015 Jan 27;65(3):311-2. doi: 10.1016/j.jacc.2014.09.084. — View Citation

Coelho T, Adams D, Silva A, Lozeron P, Hawkins PN, Mant T, Perez J, Chiesa J, Warrington S, Tranter E, Munisamy M, Falzone R, Harrop J, Cehelsky J, Bettencourt BR, Geissler M, Butler JS, Sehgal A, Meyers RE, Chen Q, Borland T, Hutabarat RM, Clausen VA, Alvarez R, Fitzgerald K, Gamba-Vitalo C, Nochur SV, Vaishnaw AK, Sah DW, Gollob JA, Suhr OB. Safety and efficacy of RNAi therapy for transthyretin amyloidosis. N Engl J Med. 2013 Aug 29;369(9):819-29. doi: 10.1056/NEJMoa1208760. — View Citation

Falk RH. Diagnosis and management of the cardiac amyloidoses. Circulation. 2005 Sep 27;112(13):2047-60. Review. — View Citation

Gillmore JD, Maurer MS, Falk RH, Merlini G, Damy T, Dispenzieri A, Wechalekar AD, Berk JL, Quarta CC, Grogan M, Lachmann HJ, Bokhari S, Castano A, Dorbala S, Johnson GB, Glaudemans AW, Rezk T, Fontana M, Palladini G, Milani P, Guidalotti PL, Flatman K, Lane T, Vonberg FW, Whelan CJ, Moon JC, Ruberg FL, Miller EJ, Hutt DF, Hazenberg BP, Rapezzi C, Hawkins PN. Nonbiopsy Diagnosis of Cardiac Transthyretin Amyloidosis. Circulation. 2016 Jun 14;133(24):2404-12. doi: 10.1161/CIRCULATIONAHA.116.021612. Epub 2016 Apr 22. — View Citation

González-López E, Gallego-Delgado M, Guzzo-Merello G, de Haro-Del Moral FJ, Cobo-Marcos M, Robles C, Bornstein B, Salas C, Lara-Pezzi E, Alonso-Pulpon L, Garcia-Pavia P. Wild-type transthyretin amyloidosis as a cause of heart failure with preserved ejection fraction. Eur Heart J. 2015 Oct 7;36(38):2585-94. doi: 10.1093/eurheartj/ehv338. Epub 2015 Jul 28. — View Citation

Kim WK, Rolf A, Liebetrau C, Van Linden A, Blumenstein J, Kempfert J, Bachmann G, Nef H, Hamm C, Walther T, Möllmann H. Detection of myocardial injury by CMR after transcatheter aortic valve replacement. J Am Coll Cardiol. 2014 Jul 29;64(4):349-57. doi: 10.1016/j.jacc.2014.03.052. — View Citation

Kvidal P, Bergström R, Hörte LG, Ståhle E. Observed and relative survival after aortic valve replacement. J Am Coll Cardiol. 2000 Mar 1;35(3):747-56. — View Citation

Lindroos M, Kupari M, Heikkilä J, Tilvis R. Prevalence of aortic valve abnormalities in the elderly: an echocardiographic study of a random population sample. J Am Coll Cardiol. 1993 Apr;21(5):1220-5. — View Citation

Nietlispach F, Webb JG, Ye J, Cheung A, Lichtenstein SV, Carere RG, Gurvitch R, Thompson CR, Ostry AJ, Matzke L, Allard MF. Pathology of transcatheter valve therapy. JACC Cardiovasc Interv. 2012 May;5(5):582-590. doi: 10.1016/j.jcin.2012.03.012. — View Citation

Perugini E, Guidalotti PL, Salvi F, Cooke RM, Pettinato C, Riva L, Leone O, Farsad M, Ciliberti P, Bacchi-Reggiani L, Fallani F, Branzi A, Rapezzi C. Noninvasive etiologic diagnosis of cardiac amyloidosis using 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid scintigraphy. J Am Coll Cardiol. 2005 Sep 20;46(6):1076-84. — View Citation

Richards DB, Cookson LM, Berges AC, Barton SV, Lane T, Ritter JM, Fontana M, Moon JC, Pinzani M, Gillmore JD, Hawkins PN, Pepys MB. Therapeutic Clearance of Amyloid by Antibodies to Serum Amyloid P Component. N Engl J Med. 2015 Sep 17;373(12):1106-14. doi: 10.1056/NEJMoa1504942. Epub 2015 Jul 15. — View Citation

Tanskanen M, Peuralinna T, Polvikoski T, Notkola IL, Sulkava R, Hardy J, Singleton A, Kiuru-Enari S, Paetau A, Tienari PJ, Myllykangas L. Senile systemic amyloidosis affects 25% of the very aged and associates with genetic variation in alpha2-macroglobulin and tau: a population-based autopsy study. Ann Med. 2008;40(3):232-9. doi: 10.1080/07853890701842988. — View Citation

Treibel TA, Bandula S, Fontana M, White SK, Gilbertson JA, Herrey AS, Gillmore JD, Punwani S, Hawkins PN, Taylor SA, Moon JC. Extracellular volume quantification by dynamic equilibrium cardiac computed tomography in cardiac amyloidosis. J Cardiovasc Comput Tomogr. 2015 Nov-Dec;9(6):585-92. doi: 10.1016/j.jcct.2015.07.001. Epub 2015 Jul 10. — View Citation

* Note: There are 15 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Patient mortality	From patient notes, GP records or Office of National Statistics.	1-year
Secondary	Major adverse cardiovascular events (MACE)	From patient's medical records. Includes for example: cardiac death, myocardial infarction and emergency cardiac surgery or intervention.	1-year
Secondary	Length of hospital stay	From patient's medical records	1-year
Secondary	Pacemaker implantation	From patient's medical records	1-year
Secondary	Outcome of the various cardiac imaging modalities		1-year